These replacement razor blades for the double-edged safety razor make sure your blade is never dull and your shave is always as close and clean as possible. All Derby Razor Blades made with stainless steel from Sweden then perforated, hardened and ground by utilizing the most state-of-the-art equipment. Their cutting edges are deposited with chromium-ceramic, platinum and tungsten, and are reviewed through strict quality control inspections at every stage of the manufacturing process for an ideal, dull-resistant sharpness. Includes: 4 packs of 5 blades (20 blades in total) Compatible with Double Edge Safety Razor Handles. These blades are not compatible with Cartridge Razor Handles.